I wouldn’t consider a romhack to be a legitimate shiny, if it modified how it works.

1/8192; it’s super rare and that’s what makes it cool IMHO.

I recently had the idea to set up an automaton on my phone to randomly draw a number from 1 to 8192 every day at 2AM. If it’s one, it sets me a reminder at 6AM to let me know today is a shiny day.

Doesn’t mean anything, and it’d statistically likely be 11 years before it happens, but what a fun thing it’ll be whenever it happens.